/*
 * Copyright 2012 The Netty Project
 *
 * The Netty Project licenses this file to you under the Apache License,
 * version 2.0 (the "License"); you may not use this file except in compliance
 * with the License. You may obtain a copy of the License at:
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations
 * under the License.
 */
package io.netty.channel.socket;

import io.netty.buffer.ByteBufAllocator;
import io.netty.channel.ChannelException;
import io.netty.channel.ChannelOption;
import io.netty.channel.DefaultChannelConfig;
import io.netty.channel.FixedRecvByteBufAllocator;
import io.netty.channel.MessageSizeEstimator;
import io.netty.channel.RecvByteBufAllocator;
import io.netty.channel.WriteBufferWaterMark;
import io.netty.util.internal.PlatformDependent;
import io.netty.util.internal.logging.InternalLogger;
import io.netty.util.internal.logging.InternalLoggerFactory;

import java.io.IOException;
import java.net.DatagramSocket;
import java.net.InetAddress;
import java.net.MulticastSocket;
import java.net.NetworkInterface;
import java.net.SocketException;
import java.util.Map;

import static io.netty.channel.ChannelOption.*;

/**
 * The default {@link DatagramChannelConfig} implementation.
 */
public class DefaultDatagramChannelConfig extends DefaultChannelConfig
        implements DatagramChannelConfig
{

    private static final InternalLogger logger = InternalLoggerFactory
            .getInstance(DefaultDatagramChannelConfig.class);

    private final DatagramSocket javaSocket;

    private volatile boolean activeOnOpen;

    /**
     * Creates a new instance.
     */
    public DefaultDatagramChannelConfig(DatagramChannel channel,
            DatagramSocket javaSocket)
    {
        super(channel, new FixedRecvByteBufAllocator(2048));
        if (javaSocket == null)
        {
            throw new NullPointerException("javaSocket");
        }
        this.javaSocket = javaSocket;
    }

    @Override
    @SuppressWarnings("deprecation")
    public Map<ChannelOption<?>, Object> getOptions()
    {
        return getOptions(super.getOptions(), SO_BROADCAST, SO_RCVBUF,
                SO_SNDBUF, SO_REUSEADDR, IP_MULTICAST_LOOP_DISABLED,
                IP_MULTICAST_ADDR, IP_MULTICAST_IF, IP_MULTICAST_TTL, IP_TOS,
                DATAGRAM_CHANNEL_ACTIVE_ON_REGISTRATION);
    }

    @Override
    @SuppressWarnings(
    { "unchecked", "deprecation" })
    public <T> T getOption(ChannelOption<T> option)
    {
        if (option == SO_BROADCAST)
        {
            return (T) Boolean.valueOf(isBroadcast());
        }
        if (option == SO_RCVBUF)
        {
            return (T) Integer.valueOf(getReceiveBufferSize());
        }
        if (option == SO_SNDBUF)
        {
            return (T) Integer.valueOf(getSendBufferSize());
        }
        if (option == SO_REUSEADDR)
        {
            return (T) Boolean.valueOf(isReuseAddress());
        }
        if (option == IP_MULTICAST_LOOP_DISABLED)
        {
            return (T) Boolean.valueOf(isLoopbackModeDisabled());
        }
        if (option == IP_MULTICAST_ADDR)
        {
            return (T) getInterface();
        }
        if (option == IP_MULTICAST_IF)
        {
            return (T) getNetworkInterface();
        }
        if (option == IP_MULTICAST_TTL)
        {
            return (T) Integer.valueOf(getTimeToLive());
        }
        if (option == IP_TOS)
        {
            return (T) Integer.valueOf(getTrafficClass());
        }
        if (option == DATAGRAM_CHANNEL_ACTIVE_ON_REGISTRATION)
        {
            return (T) Boolean.valueOf(activeOnOpen);
        }
        return super.getOption(option);
    }

    @Override
    @SuppressWarnings("deprecation")
    public <T> boolean setOption(ChannelOption<T> option, T value)
    {
        validate(option, value);

        if (option == SO_BROADCAST)
        {
            setBroadcast((Boolean) value);
        }
        else if (option == SO_RCVBUF)
        {
            setReceiveBufferSize((Integer) value);
        }
        else if (option == SO_SNDBUF)
        {
            setSendBufferSize((Integer) value);
        }
        else if (option == SO_REUSEADDR)
        {
            setReuseAddress((Boolean) value);
        }
        else if (option == IP_MULTICAST_LOOP_DISABLED)
        {
            setLoopbackModeDisabled((Boolean) value);
        }
        else if (option == IP_MULTICAST_ADDR)
        {
            setInterface((InetAddress) value);
        }
        else if (option == IP_MULTICAST_IF)
        {
            setNetworkInterface((NetworkInterface) value);
        }
        else if (option == IP_MULTICAST_TTL)
        {
            setTimeToLive((Integer) value);
        }
        else if (option == IP_TOS)
        {
            setTrafficClass((Integer) value);
        }
        else if (option == DATAGRAM_CHANNEL_ACTIVE_ON_REGISTRATION)
        {
            setActiveOnOpen((Boolean) value);
        }
        else
        {
            return super.setOption(option, value);
        }

        return true;
    }

    private void setActiveOnOpen(boolean activeOnOpen)
    {
        if (channel.isRegistered())
        {
            throw new IllegalStateException(
                    "Can only changed before channel was registered");
        }
        this.activeOnOpen = activeOnOpen;
    }

    @Override
    public boolean isBroadcast()
    {
        try
        {
            return javaSocket.getBroadcast();
        }
        catch (SocketException e)
        {
            throw new ChannelException(e);
        }
    }

    @Override
    public DatagramChannelConfig setBroadcast(boolean broadcast)
    {
        try
        {
            // See: https://github.com/netty/netty/issues/576
            if (broadcast && !javaSocket.getLocalAddress().isAnyLocalAddress()
                    && !PlatformDependent.isWindows()
                    && !PlatformDependent.isRoot())
            {
                // Warn a user about the fact that a non-root user can't receive
                // a
                // broadcast packet on *nix if the socket is bound on
                // non-wildcard address.
                logger.warn(
                        "A non-root user can't receive a broadcast packet if the socket "
                                + "is not bound to a wildcard address; setting the SO_BROADCAST flag "
                                + "anyway as requested on the socket which is bound to "
                                + javaSocket.getLocalSocketAddress() + '.');
            }

            javaSocket.setBroadcast(broadcast);
        }
        catch (SocketException e)
        {
            throw new ChannelException(e);
        }
        return this;
    }

    @Override
    public InetAddress getInterface()
    {
        if (javaSocket instanceof MulticastSocket)
        {
            try
            {
                return ((MulticastSocket) javaSocket).getInterface();
            }
            catch (SocketException e)
            {
                throw new ChannelException(e);
            }
        }
        else
        {
            throw new UnsupportedOperationException();
        }
    }

    @Override
    public DatagramChannelConfig setInterface(InetAddress interfaceAddress)
    {
        if (javaSocket instanceof MulticastSocket)
        {
            try
            {
                ((MulticastSocket) javaSocket).setInterface(interfaceAddress);
            }
            catch (SocketException e)
            {
                throw new ChannelException(e);
            }
        }
        else
        {
            throw new UnsupportedOperationException();
        }
        return this;
    }

    @Override
    public boolean isLoopbackModeDisabled()
    {
        if (javaSocket instanceof MulticastSocket)
        {
            try
            {
                return ((MulticastSocket) javaSocket).getLoopbackMode();
            }
            catch (SocketException e)
            {
                throw new ChannelException(e);
            }
        }
        else
        {
            throw new UnsupportedOperationException();
        }
    }

    @Override
    public DatagramChannelConfig setLoopbackModeDisabled(
            boolean loopbackModeDisabled)
    {
        if (javaSocket instanceof MulticastSocket)
        {
            try
            {
                ((MulticastSocket) javaSocket)
                        .setLoopbackMode(loopbackModeDisabled);
            }
            catch (SocketException e)
            {
                throw new ChannelException(e);
            }
        }
        else
        {
            throw new UnsupportedOperationException();
        }
        return this;
    }

    @Override
    public NetworkInterface getNetworkInterface()
    {
        if (javaSocket instanceof MulticastSocket)
        {
            try
            {
                return ((MulticastSocket) javaSocket).getNetworkInterface();
            }
            catch (SocketException e)
            {
                throw new ChannelException(e);
            }
        }
        else
        {
            throw new UnsupportedOperationException();
        }
    }

    @Override
    public DatagramChannelConfig setNetworkInterface(
            NetworkInterface networkInterface)
    {
        if (javaSocket instanceof MulticastSocket)
        {
            try
            {
                ((MulticastSocket) javaSocket)
                        .setNetworkInterface(networkInterface);
            }
            catch (SocketException e)
            {
                throw new ChannelException(e);
            }
        }
        else
        {
            throw new UnsupportedOperationException();
        }
        return this;
    }

    @Override
    public boolean isReuseAddress()
    {
        try
        {
            return javaSocket.getReuseAddress();
        }
        catch (SocketException e)
        {
            throw new ChannelException(e);
        }
    }

    @Override
    public DatagramChannelConfig setReuseAddress(boolean reuseAddress)
    {
        try
        {
            javaSocket.setReuseAddress(reuseAddress);
        }
        catch (SocketException e)
        {
            throw new ChannelException(e);
        }
        return this;
    }

    @Override
    public int getReceiveBufferSize()
    {
        try
        {
            return javaSocket.getReceiveBufferSize();
        }
        catch (SocketException e)
        {
            throw new ChannelException(e);
        }
    }

    @Override
    public DatagramChannelConfig setReceiveBufferSize(int receiveBufferSize)
    {
        try
        {
            javaSocket.setReceiveBufferSize(receiveBufferSize);
        }
        catch (SocketException e)
        {
            throw new ChannelException(e);
        }
        return this;
    }

    @Override
    public int getSendBufferSize()
    {
        try
        {
            return javaSocket.getSendBufferSize();
        }
        catch (SocketException e)
        {
            throw new ChannelException(e);
        }
    }

    @Override
    public DatagramChannelConfig setSendBufferSize(int sendBufferSize)
    {
        try
        {
            javaSocket.setSendBufferSize(sendBufferSize);
        }
        catch (SocketException e)
        {
            throw new ChannelException(e);
        }
        return this;
    }

    @Override
    public int getTimeToLive()
    {
        if (javaSocket instanceof MulticastSocket)
        {
            try
            {
                return ((MulticastSocket) javaSocket).getTimeToLive();
            }
            catch (IOException e)
            {
                throw new ChannelException(e);
            }
        }
        else
        {
            throw new UnsupportedOperationException();
        }
    }

    @Override
    public DatagramChannelConfig setTimeToLive(int ttl)
    {
        if (javaSocket instanceof MulticastSocket)
        {
            try
            {
                ((MulticastSocket) javaSocket).setTimeToLive(ttl);
            }
            catch (IOException e)
            {
                throw new ChannelException(e);
            }
        }
        else
        {
            throw new UnsupportedOperationException();
        }
        return this;
    }

    @Override
    public int getTrafficClass()
    {
        try
        {
            return javaSocket.getTrafficClass();
        }
        catch (SocketException e)
        {
            throw new ChannelException(e);
        }
    }

    @Override
    public DatagramChannelConfig setTrafficClass(int trafficClass)
    {
        try
        {
            javaSocket.setTrafficClass(trafficClass);
        }
        catch (SocketException e)
        {
            throw new ChannelException(e);
        }
        return this;
    }

    @Override
    public DatagramChannelConfig setWriteSpinCount(int writeSpinCount)
    {
        super.setWriteSpinCount(writeSpinCount);
        return this;
    }

    @Override
    public DatagramChannelConfig setConnectTimeoutMillis(
            int connectTimeoutMillis)
    {
        super.setConnectTimeoutMillis(connectTimeoutMillis);
        return this;
    }

    @Override
    @Deprecated
    public DatagramChannelConfig setMaxMessagesPerRead(int maxMessagesPerRead)
    {
        super.setMaxMessagesPerRead(maxMessagesPerRead);
        return this;
    }

    @Override
    public DatagramChannelConfig setAllocator(ByteBufAllocator allocator)
    {
        super.setAllocator(allocator);
        return this;
    }

    @Override
    public DatagramChannelConfig setRecvByteBufAllocator(
            RecvByteBufAllocator allocator)
    {
        super.setRecvByteBufAllocator(allocator);
        return this;
    }

    @Override
    public DatagramChannelConfig setAutoRead(boolean autoRead)
    {
        super.setAutoRead(autoRead);
        return this;
    }

    @Override
    public DatagramChannelConfig setAutoClose(boolean autoClose)
    {
        super.setAutoClose(autoClose);
        return this;
    }

    @Override
    public DatagramChannelConfig setWriteBufferHighWaterMark(
            int writeBufferHighWaterMark)
    {
        super.setWriteBufferHighWaterMark(writeBufferHighWaterMark);
        return this;
    }

    @Override
    public DatagramChannelConfig setWriteBufferLowWaterMark(
            int writeBufferLowWaterMark)
    {
        super.setWriteBufferLowWaterMark(writeBufferLowWaterMark);
        return this;
    }

    @Override
    public DatagramChannelConfig setWriteBufferWaterMark(
            WriteBufferWaterMark writeBufferWaterMark)
    {
        super.setWriteBufferWaterMark(writeBufferWaterMark);
        return this;
    }

    @Override
    public DatagramChannelConfig setMessageSizeEstimator(
            MessageSizeEstimator estimator)
    {
        super.setMessageSizeEstimator(estimator);
        return this;
    }
}
